Headphone



FIG. 1 is a perspective view of a headphone showing our new design;

FIG. 2 is a left side elevational view thereof;

FIG. 3 is a right side elevational view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a back view of the new design;

FIG. 6 is a bottom view thereof; and,

FIG. 7 is a top plan view thereof.

The broken lines form no part of the claimed design. 

The ornamental design for a headphone, as shown and described. 